The Sailor Moon manga series features an extensive cast of characters created by Naoko Takeuchi. The series takes place in Tokyo, Japan, where the Sailor Guardians (セーラー戦士, Sērā Senshi), a group of ten magical girls, are formed to combat an assortment of antagonists attempting to take over the Earth, the Solar System, and the Milky Way galaxy. Each Guardian undergoes a transformation which grants her a uniform in her own theme colors and a unique elemental power. The ten Sailor Guardians are named after the planets of the Solar System, with the exception of Earth but including its moon. While many of the characters are humans with superhuman strength and magical abilities, the cast also includes anthropomorphic animals and extraterrestrial lifeforms.